Rear body structure

Abstract

To provide a vehicle frame structure that can achieve weight reduction and improved freedom of vehicle body design. [Solution] The rear body structure (1) comprises a rear wheel house section (10) and a rear frame connecting section (26) to which a rear frame (40) is connected, which are integrally formed by die-cast molding, the rear wheel house section (10) having a bulge section (11) that bulges inward in the vehicle width direction to cover the rear wheel (3), and at least a portion of the rear frame connecting section (26) is positioned forward of the rear end of the bulge section (11).

Description

[Technical Field]

[0001] The present invention relates to a rear structure of a vehicle body. [Background technology]

[0002] In recent years, research and development has been conducted into weight reduction that contributes to energy efficiency in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy. Meanwhile, Patent Document 1 discloses a die-cast rear floor body structure that integrates a pair of left and right rear wheel covers, a pair of left and right vertical beams that are provided along the lower ends of the rear wheel covers, a connecting beam that connects the pair of left and right vertical beams, and a pair of front and rear horizontal beams. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Chinese Patent Application Publication No. 117360634 Summary of the Invention [Problem to be solved by the invention]

[0004] In this structure, the rear frame is connected to the die-cast rear floor body structure behind the rear wheel cover (rear wheel house), which increases the overall length of the vehicle body (rear overhang), increasing weight and reducing the freedom of vehicle design.

[0005] The present invention has been made in consideration of the above points, and its objective is to provide a vehicle frame structure that can achieve weight reduction and increased freedom in vehicle body design, and ultimately contribute to energy efficiency. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the rear body structure of the present invention is a rear body structure that has a rear wheel house section and a rear frame connecting section to which a rear frame is connected, which are integrally formed by die-cast molding, and is characterized in that the rear wheel house section has a bulge section that bulges inward in the vehicle width direction to cover the rear wheel, and at least a portion of the rear frame connecting section is positioned forward of the rear end of the bulge section. [Effects of the Invention]

[0007] According to the present invention, it is possible to reduce the weight of the rear structure of the vehicle body and improve the degree of freedom in vehicle body design, which in turn can contribute to improving energy efficiency. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram schematically illustrating a vehicle rear body structure according to an embodiment of the present invention, and is a perspective view seen from diagonally above and front. [Figure 2] 1 is a diagram schematically illustrating a vehicle rear body structure according to an embodiment of the present invention, and is a perspective view seen from diagonally above and rearward. [Figure 3] 1 is a side view schematically showing a vehicle rear body structure according to an embodiment of the present invention; [Figure 4] 1 is a plan view schematically showing a vehicle rear body structure according to an embodiment of the present invention; [Figure 5] 1 is a bottom view schematically showing a vehicle rear body structure according to an embodiment of the present invention; [Figure 6] FIG. 4 is a perspective view schematically showing a rear frame connecting portion and an opposing rib. [Figure 7] FIG. 7 is an enlarged view of part VII in FIG. 5. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 4. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] 1 is a diagram schematically illustrating a vehicle rear body structure according to an embodiment of the present invention, and is a bottom view illustrating a state in which a drive unit is attached. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Next, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, "front and rear" refers to the front-rear direction in the direction of travel of the vehicle (the front-rear direction of the vehicle body), and "left and right" refers to the left and right direction (the vehicle width direction) as seen from the driver's seat.

[0010] As shown in Figures 1 and 2, a vehicle rear structure 1 according to an embodiment of the present invention is configured by a die-cast product formed by a die-cast method (aluminum die-cast method) using aluminum as the material, at least a portion of which is a die-cast product. The vehicle rear structure 1 integrally includes a pair of left and right rear wheel housing sections 10 and a rear floor panel section 20 connecting the pair of left and right rear wheel housing sections 10 as a die-cast section 2. The vehicle rear structure 1 also includes a pair of left and right rear frames 40 (see Figure 3) as separate members from the die-cast section 2.

[0011] <Rear wheel house> The rear wheel house portion 10 integrally includes a bulging portion 11, a flange portion 12, and a plurality of ribs 13.

[0012] The bulging portion 11 is a rear wheel house main body that bulges inward in the vehicle width direction. The bulging portion 11 accommodates the upper portion of the rear wheel 3 (see FIG. 3) of the vehicle on the outer side in the vehicle width direction.

[0013] The flange portion 12 extends outward from the outer end of the bulging portion 11 in the vehicle width direction.

[0014] The rib 13 extends outward in the vehicle width direction from the bulging portion 11 .

[0015] <Rear floor panel> The rear floor panel portion 20 is a plate-shaped portion provided to connect the bulging portions 11 of the pair of left and right rear wheel house portions 10. The rear floor panel portion 20 includes an upper wall portion 21, a front wall portion 22, a first lower wall portion 23, a rear wall portion 24, and a second lower wall portion 25 as a rear floor panel main body portion.

[0016] ≪Top wall section≫ The upper wall portion 21 extends in the front-rear direction and the vehicle width direction.

[0017] ≪Front wall section≫ The front wall portion 22 extends downward from the front end portion of the upper wall portion 21 .

[0018] ≪First outer wall section≫ The first lower wall portion 23 extends forward from the lower end portion of the front wall portion 22. A vehicle width direction intermediate portion of the first lower wall portion 23 forms a flange portion relative to the front wall portion 22. A vehicle width direction end portion of the first lower wall portion 23 extends forward of the rear wheel house portion 10.

[0019] ≪Back wall section≫ The rear wall portion 24 extends downward from the rear end portion of the upper wall portion 21 .

[0020] ≪Second lower wall section≫ The second lower wall portion 25 extends rearward from the lower end of the rear wall portion 24. The vehicle width direction end of the second lower wall portion 25 extends rearward of the rear wheel house portion 10. The rear end of the vehicle width direction middle portion of the second lower wall portion 25 is located forward of the rear end of the rear wheel house portion 10 (bulge portion 11) and forms a notch 25a. The notch 25a is intended to ensure space for arranging components. The surface precision of the second lower wall portion 25 is improved by performing a cutting process after casting.

[0021] <Rear frame connection part> As shown in FIGS. 4 and 6, the rear floor panel portion 20 includes a pair of left and right rear frame connecting portions 26 as portions to which the rear frames 40 are connected.

[0022] The rear frame connecting portion 26 is a recess that is recessed forward and is formed across the rear wall portion 24 and the second lower wall portion 25. The rear frame connecting portion 26 includes an opposing wall portion 26a, an outer wall portion 26b, an inner wall portion 26c, and a lower wall portion 26d.

[0023] The opposing wall portion 26a is a part of the rear wall portion 24 of the rear floor panel main body, and extends in the vehicle width direction and the up-down direction.

[0024] The outer wall portion 26b is a part of the rear wall portion 24 of the rear floor panel main body, and extends rearward from the outer end portion in the vehicle width direction of the opposing wall portion 26a. The rear frame 40 is connected to the outer wall portion 26b by bolting or the like.

[0025] In this embodiment, the outer wall portion 26b is formed with a protrusion (base portion) 26b1 that protrudes inward in the vehicle width direction. The tip end of the rear frame 40 is fixed to the protrusion 26b1 by a bolt that is inserted into a hole formed in the tip surface of the protrusion 26b1 on the inner side in the vehicle width direction. The head of the bolt is accommodated in a space on the outer side of the protrusion 26b1 in the vehicle width direction.

[0026] The inner wall portion 26c is a part of the rear wall portion 24 of the rear floor panel main body, and extends rearward from the inner end of the opposing wall portion 26a in the vehicle width direction. The inner wall portion 26c is inclined inward in the vehicle width direction as it extends rearward. The rear frame 40 is connected to the inner wall portion 26c by bolting or the like.

[0027] In this embodiment, the inner wall portion 26c is formed with a protrusion (seat portion) 26c1 that protrudes rearward. The tip end of the rear frame 40 (more specifically, a flange portion (not shown) attached to the tip end of the rear frame 40) is fixed to the protrusion 26c1 with a bolt inserted into a hole formed in the rear tip surface of the protrusion 26c1.

[0028] The lower wall portion 26d is a part of the second lower wall portion 25 of the rear floor panel main body, and extends rearward from the lower end of the opposing wall portion 26a. The lower wall portion 26d connects the lower ends of the outer wall portion 26b and the inner wall portion 26c.

[0029] The rear frame connecting portion 26 is located at the rear of the rear floor panel main body, forward of the notch 25a which serves as the rear end of the rear floor panel main body. The rear frame connecting portion 26 is also provided inward in the vehicle width direction from the inner end of the bulge 11, and at least a portion of the rear frame connecting portion 26 is disposed forward of the rear end of the bulge 11. Therefore, the vehicle body rear structure 1 can shorten the rear overhang of the vehicle body, thereby achieving weight reduction and improving the freedom of vehicle body design.

[0030] The rear frame connecting portion 26 and the front end portion 41 of the rear frame 40 are located forward of the rear end portion of the drive unit 4. The rear portion of the drive unit 4 is disposed between the pair of left and right rear frames 40.

[0031] <Rib structure> As shown in FIGS. 4 and 5, the rear floor panel main body of the rear floor panel portion 20 is formed with a plurality of ribs for improving the rigidity of the rear floor panel main body, for load transmission, and for absorbing collision energy.

[0032] <Rib structure on the top side> As shown in Fig. 4, the rear floor panel portion 20 has ribs erected on its upper surface (inside the vehicle compartment), including multiple left and right ribs 31, multiple front and rear ribs 32, multiple annular ribs 33, and a pair of left and right opposing ribs 34. These ribs transmit loads in the direction along the ribs and can absorb collision energy. In the following description, the front and rear ribs 32a, 32c, 37a, 37b, 37c (see Fig. 5), which are inclined inward in the vehicle width direction as they extend forward, are referred to as load transmission ribs.

[0033] <Left and right ribs> The left and right ribs 31 are erected upward from the upper wall portion 21 of the rear floor panel main body and extend in the vehicle width direction. In this embodiment, both ends of the left and right ribs 31 in the vehicle width direction are connected to the bulging portions 11 of the rear wheel house portion 10, respectively.

[0034] <Front and back ribs> The front and rear ribs 32 are erected upward from the upper wall 21, the front wall 22, and the first lower wall 23 of the rear floor panel main body (they are erected forward from the front wall 22) and extend in the front-rear direction. Of the multiple front and rear ribs 32, the front and rear ribs 32 located on the outer sides in the vehicle width direction are inclined outward in the vehicle width direction as they extend forward.

[0035] <Load transfer rib / upper rib> Of the multiple front and rear ribs 32, a pair of left and right front and rear ribs 32a on the inner side in the vehicle width direction are load transfer ribs (upper ribs) that incline toward the inside in the vehicle width direction as they extend forward. The rear ends of the front and rear ribs 32a are located forward of the rear frame connecting portion 26. In this embodiment, the rear ends of the front and rear ribs 32a are connected to the opposing wall portion 26a of the rear frame connecting portion 26. The front portions of the front and rear ribs 32a extend in the front-to-rear direction.

[0036] The pair of left and right front and rear ribs 32c located on the outer side in the vehicle width direction of the pair of left and right front and rear ribs 32a are load transmission ribs (upper ribs) that are inclined so as to approach inward in the vehicle width direction as they extend forward. The rear end portions of the front-rear ribs 32c are located in front of the rear frame connecting portion 26. In this embodiment, the rear end portions of the front-rear ribs 32c are connected to the opposing wall portion 26a of the rear frame connecting portion 26. The rear portions of the front-rear ribs 32a extend in the front-rear direction.

[0037] The angle θ of the inclined portions of the front and rear ribs 32a, 32c relative to the front and rear direction is 30 degrees or less (for example, 30 degrees).

[0038] ≪Annular rib≫ The annular rib 33 has a cylindrical shape in a plan view and is provided in front of the rear frame connecting portion 26. In this embodiment, the annular rib 33 connects the front-rear rib 32a, which serves as a load transmission rib, the front-rear rib 32 adjacent to the front-rear rib 32a, and the left-right ribs 31. In other words, the front-rear rib 32a, the front-rear rib 32 adjacent to the front-rear rib 32a, and the left-right ribs 31 are formed to extend radially from the annular rib 33. In other words, the front-rear rib 32a, the front-rear rib 32 adjacent to the front-rear rib 32a, and the left-right ribs 31 are divided into front-rear or left-right by the annular rib 33.

[0039] <Opposing ribs> The opposing ribs 34 extend rearward from the opposing wall portions 26a of the rear frame connecting portions 26. In this embodiment, the opposing ribs 34 have a lattice shape (e.g., a honeycomb shape) when viewed from the rear. The rear ends of the opposing ribs 34 face the front ends of the rear frames 40 at a distance.

[0040] <Rib structure on the underside> As shown in FIG. 5, the rear floor panel portion 20 has ribs erected on its underside (outside the vehicle compartment), including a plurality of left and right ribs 36, a plurality of front and rear ribs 37, a plurality of annular ribs 38, and a reinforcing rib 39.

[0041] <Left and right ribs> The left and right ribs 36 are erected downward from the upper wall portion 21 of the rear floor panel main body at positions corresponding to the upper left and right ribs 31 and extend in the vehicle width direction.

[0042] <Front and back ribs> The front and rear ribs 37 are erected downward from the upper wall 21, front wall 22 and first lower wall 23 of the rear floor panel main body at positions corresponding to the upper front and rear ribs 32 and at other positions (they are erected rearward from the front wall 22) and extend in the front-to-rear direction. Of the multiple front and rear ribs 37, the front and rear ribs 37 located on the outer sides in the vehicle width direction are inclined outward in the vehicle width direction as they extend forward.

[0043] <Load transfer rib / lower rib> Of the multiple front and rear ribs 37, a pair of left and right front and rear ribs 37a on the inner side in the vehicle width direction are load transfer ribs (lower ribs) that are inclined toward the inside in the vehicle width direction as they extend forward at positions corresponding to the upper front and rear ribs 32a. The rear ends of the front and rear ribs 37a are located forward of the rear frame connecting portion 26. In this embodiment, the rear ends of the front and rear ribs 37a are connected to the opposing wall portion 26a of the rear frame connecting portion 26. The front ends of the front and rear ribs 32a extend in the front-to-rear direction.

[0044] The front-rear rib 37b adjacent to the front-rear rib 37a is a load-transmitting rib (lower rib) that slopes inward in the vehicle width direction as it extends forward. The rear ends of the front-rear ribs 37b are located forward of the rear frame connecting portion 26. In this embodiment, the rear ends of the front-rear ribs 37b are connected to the annular rib 38.

[0045] The pair of left and right front and rear ribs 37b located outside the pair of left and right front and rear ribs 37b in the vehicle width direction are load transmission ribs (lower ribs) that slope inward in the vehicle width direction as they extend forward. The rear end portions of the front and rear ribs 37c are located in front of the rear frame connecting portion 26. In this embodiment, the rear end portions of the front and rear ribs 37c are connected to the opposing wall portion 26a of the rear frame connecting portion 26. The rear portions of the front and rear ribs 37b extend in the front-to-rear direction.

[0046] The angle θ of the inclined portions of the front and rear ribs 37a, 37b relative to the front and rear direction is 30 degrees or less (for example, 30 degrees for the front and rear ribs 37a, 37c, and 15 degrees for the front and rear rib 37b).

[0047] ≪Annular rib≫ 7, the annular rib 38 has a cylindrical shape in a plan view and is provided in front of the rear frame connecting portion 26. In this embodiment, the annular rib 38 connects the front and rear ribs 37a, 37b serving as load transmission ribs, the front and rear rib 37 adjacent to the front and rear rib 37b, and the left and right ribs 36. In other words, the front and rear ribs 37a, 37b, the front and rear ribs 37 adjacent to the front and rear ribs 37b, and the left and right ribs 36 are formed to extend radially from the annular rib 38. In other words, the front and rear ribs 37a, 37b, and the left and right ribs 36 adjacent to the front and rear ribs 37a, 37b are divided into front and rear or left and right by the annular rib 38.

[0048] <Reinforcing rib> As shown in FIG. 5, the reinforcing ribs 39 improve the rigidity of the rear floor panel portion 20 and extend downward from the upper wall portion 21 in an area surrounded by the pair of front and rear left and right ribs 36 and the pair of left and right front and rear ribs 37a. The reinforcing ribs 39 have a lattice shape (e.g., a honeycomb shape) when viewed from the bottom. In this embodiment, the reinforcing ribs 39 are connected to the pair of front and rear left and right ribs 36 and the pair of left and right front and rear ribs 37a. Note that the reinforcing ribs 39 are not limited to a lattice shape, and may be ribs arranged only in the front-rear direction, ribs arranged only in the left-right direction, or a mixture of these and irregularly arranged ribs.

[0049] <Upper and lower load transfer ribs> As shown in FIGS. 4 and 5, the load transmission ribs extending inward in the vehicle width direction toward the front are more numerous than the upper front and rear ribs 32a and 32c.

[0050] 8, in the front and rear ribs 32a, 37a serving as load transmission ribs that extend inward in the vehicle width direction as they extend forward, the erect height H2 of the lower front and rear rib 37a is greater than the erect height H1 of the upper front and rear rib 32a. Note that this height relationship can also be applied to the other front and rear ribs 32, 37, the left and right ribs 31, 36, and the annular ribs 33, 38.

[0051] The vehicle body rear structure 1 can suppress pooling of electrodeposition paint and prevent deterioration of painting quality by making the upper front and rear ribs 32a lower than the lower front and rear ribs 37a and making the upper front and rear ribs 32a smaller than the lower front and rear ribs 37a, 37b.

[0052] As described above, the front and rear ribs 32a, 32c, 37a, 37b, and 37c serving as load transmission ribs need only be able to transmit forward the rear collision load input to the rear frame connecting portion 26. In other words, the rear ends of the front and rear ribs 32a, 32c, 37a, 37b, and 37c may be connected to (the opposing wall portion 26a of) the rear frame connecting portion 26, or may be located in front of (the opposing wall portion 26a of) the rear frame connecting portion 26 and spaced apart from (the opposing wall portion 26a of) the rear frame connecting portion 26.

[0053] <Rear frame> As shown in Figures 3 and 4, the rear frame 40 is a metallic tubular member extending in the front-rear direction. The rear frame 40 has a closed cross-sectional shape (an octagonal shape in this embodiment) when viewed from the front. The rear frame 40 extends rearward from the rear floor panel portion 20. The front portion of the rear frame 40 overlaps with the rear floor panel portion 20 in a plan view, and the rear portion of the rear frame 40 protrudes rearward from the rear floor panel portion 20 in a plan view. A front end portion 41 of the rear frame 40 is connected to the rear frame connecting portion 26. A bumper beam (not shown) is installed between the rear ends of the pair of left and right rear frames 40.

[0054] As shown in Figure 9, the vehicle width distance W2 between the rear frame 40 and rear frame connecting portion 26 on one side in the vehicle width direction (e.g., the left side) and the vehicle body end on the other side in the vehicle width direction (e.g., the right side) is located at a position within 70% (and greater than 50%) of the overall vehicle body width W1.

[0055] <Rear frame mounting structure> 4 and 6, the front end 41 of the rear frame 40 is connected to the rear frame connecting portion 26 in a state where it faces the opposing rib 34 at a distance. That is, the outer wall portion of the front end 41 of the rear frame 40 is attached to the outer wall portion 26b of the rear frame connecting portion 26 by fastening bolts. Here, the convex portion 26b1 of the outer wall portion 26b is integrated with the lower part of the bulging portion 11 and is accessible from the outer side of the bulging portion 11 in the vehicle width direction. Therefore, the bolt fastening can be performed using a jig X from the outer side of the bulging portion 11 of the rear wheel house portion 10 in the vehicle width direction (see FIG. 9).

[0056] 3, the rear frame connecting portion 26, i.e., the front end portion 41 of the rear frame 40 connected to the rear frame connecting portion 26, is positioned so as to overlap the rear wheel 3 in a side view. The front end portion 41 of the rear frame 40 may be positioned so as to overlap the wheel 3a of the rear wheel 3, or may be positioned so as to overlap the tire 3b of the rear wheel 3 in a side view. In this embodiment, the portion of the outer wall portion 26b to which the rear frame 40 is connected is positioned so as to overlap the tire 3b of the rear wheel 3 in a side view, and is accessible from the vehicle outer side of the bulging portion 11 of the rear wheel house portion 10 (the space that accommodates the rear wheel 3, which is configured on the vehicle widthwise outer side of the bulging portion 11).

[0057] 4 and 6, the inner wall portion of the front end portion 41 of the rear frame 40 is attached by bolts to the inner wall portion 26c of the rear frame connecting portion 26 via a flange member (not shown). The bolts can be fastened from behind the inner wall portion 26c.

[0058] <Drive unit mounting structure> 10, the drive unit 4 includes a power source (e.g., a motor) 4a for rotating the pair of left and right rear wheels 3, and a pair of left and right transmission parts (e.g., shafts) 4b for transmitting the rotational force of the power source 4a to the rear wheels 3. The drive unit 4, more specifically, the power source 4a of the drive unit 4, is disposed below the upper wall 21 in an area surrounded by the upper wall 21, the front wall 22, and the rear wall 24, and is attached to a plurality of drive unit mounting parts 27 by bolting or the like. The plurality of drive unit mounting parts 27 are disposed so as to surround a reinforcing rib 39, which will be described later.

[0059] The drive unit mounting portions 27 are provided on the lower wall portions 26d of the pair of left and right rear frame connecting portions 26. Since the drive unit mounting portions 27 are provided on the rear frame connecting portions 26, which have improved strength due to the connection of the rear frame 40, the drive unit 4 can be held in an appropriate manner.

[0060] <Load transfer during rear-end collision> During a rear-end collision of the vehicle, the rear-end collision load is transmitted from the pair of left and right rear frames 40 to the rear-frame connecting portion 26 of the vehicle body rear structure 1. The rear-end collision load transmitted to the rear-frame connecting portion 26 is transmitted forward while being dispersed in the vehicle width direction via the upper and lower front and rear ribs 32, 37. Therefore, the vehicle body rear structure 1 can transmit the rear-end collision load in an optimal manner, and can also absorb the collision energy optimally throughout the entire rear floor panel, including the middle portion in the vehicle width direction.

[0061] Here, in the event of a rear-end collision of the vehicle, the rear frame 40 deforms such that the rear end of the rear frame is lifted. That is, the upper front and rear ribs 32 deform in a compressive direction, and the lower front and rear ribs 37 deform in a tensile direction. In the vehicle body rear structure 1, the lower front and rear ribs 37 that deform in a tensile direction are higher and more numerous than the upper front and rear ribs 32 that deform in a compressive direction, and therefore the rear-end collision load can be suitably transmitted via the lower front and rear ribs 37 that are less likely to deform.

[0062] In addition, in the vehicle rear structure 1, the angle θ of the front and rear ribs 32a, 32c, 37a, 37b, and 37c serving as load transmission ribs relative to the fore-and-aft direction is set to 30 degrees or less, thereby suppressing deformation of the ribs and enabling rear-end collision loads to be transmitted favorably.

[0063] In addition, the vehicle rear structure 1 has improved rigidity in the vehicle widthwise central portion due to the reinforcing rib 39, which suppresses deformation of the rear floor panel main body due to a rear collision load and allows the rear collision load to be transmitted more effectively.

[0064] Furthermore, the vehicle rear body structure 1 distributes the rear collision load to the plurality of front and rear ribs 32, 37 by the annular ribs 33, 38, and therefore can transmit the rear collision load more effectively.

[0065] The vehicle rear structure 1 according to an embodiment of the present invention is a vehicle rear structure 1 that is integrally formed by die-cast molding of a rear wheel house section 10 and a rear frame connecting section 26 to which a rear frame 40 is connected, and the rear wheel house section 10 has a bulge section 11 that bulges inward in the vehicle width direction to cover the rear wheel 3, and at least a portion of the rear frame connecting section 26 is positioned forward of the rear end section of the bulge section 11. Therefore, the vehicle body rear structure 1 can shorten the rear overhang of the vehicle body by realizing the forward arrangement of the rear frame 40. In other words, the vehicle body rear structure 1 can achieve weight reduction and increased freedom in vehicle body design.

[0066] In the rear body structure 1, the rear frame connecting portion 26 is provided at a position where the vehicle width direction distance from the end of the vehicle body on the opposite side of the rear frame connecting portion 26 in the vehicle width direction is within 70% of the overall width of the vehicle body. Therefore, even in an offset rear collision, the vehicle body rear structure 1 can receive the load through both of the pair of left and right rear frames 40. In other words, the vehicle body rear structure 1 can reduce the input of the rear collision load to the left and right rear frames 40 in an offset rear collision, thereby achieving weight reduction including the rear frames 40.

[0067] In the vehicle rear body structure 1, the rear floor panel portion 20 includes opposing ribs 34 extending in the front-rear direction, and the opposing ribs 34 are provided at positions opposing the front end portions 41 of the rear frames 40. Therefore, the vehicle rear structure 1 can suitably receive and transmit a rear collision load from the rear frame 40. Furthermore, the vehicle rear structure 1 is capable of adjusting the length of the opposing rib 34 in accordance with the position of the front end 41 of the rear frame 40, thereby improving the degree of freedom in the installation position of the rear frame 40.

[0068] The rear body structure 1 comprises a pair of left and right rear wheel house sections 10 and a rear floor panel section 20 that connects the pair of left and right rear wheel house sections 10, which are integrally formed by die-cast molding, and the rear frame connecting section 26 is provided on the rear floor panel section 20. Therefore, the vehicle body rear structure 1 can improve the degree of freedom in the installation position of the rear frame connecting portion 26. Furthermore, the vehicle body rear structure 1 can distribute the rear collision load from the rear frame 40 to the left and right rear wheel house portions 10, which allows the rear frame 40 to be made smaller and the rear overhang to be shortened.

[0069] In the vehicle rear structure 1, the rear end of the rear floor panel portion 20 is located between the pair of left and right rear wheel house portions 10, forward of the rear end of the bulge portion 11 in the pair of left and right rear wheel house portions 10, and the rear frame connecting portion 26 is located forward of the rear end of the rear floor panel portion 20. Therefore, the vehicle rear structure 1 can ensure space for component placement even when the rear overhang is shortened, thereby ensuring freedom in vehicle design. Furthermore, the vehicle rear structure 1 can achieve a smaller and lighter rear floor structure by forming the pair of left and right rear wheel house sections 10 and the rear floor panel section 20 into an integrated die-cast section 2.

[0070] In the vehicle rear body structure 1, a front end portion 41 of the rear frame 40 is located forward of a rear end portion of a drive unit 4 that is disposed between the pair of left and right rear frames 40. Therefore, the vehicle rear structure 1 can shorten the rear overhang while ensuring a space for arranging the drive unit 4. Furthermore, the vehicle rear structure 1 can firmly hold the drive unit 4.

[0071] In the vehicle rear body structure 1, the rear frame connecting portion 26 is provided inward in the vehicle width direction from the inner end portion of the bulging portion 11 in the vehicle width direction. Therefore, in the vehicle rear body structure 1, the rear frame 40 can be disposed further forward.

[0072] In the vehicle rear body structure 1, the rear frame connecting portion 26 is configured to be able to connect the rear frame 40 from the vehicle exterior side of the rear wheel house portion 10. Therefore, the vehicle rear body structure 1 can prevent a decrease in the ease of installation while realizing the forward arrangement of the rear frame 40.

[0073] In the vehicle rear body structure 1, the rear frame connecting portion 26 is disposed at a position overlapping with the rear wheel 3 in a side view. Therefore, the vehicle rear structure 1 can shorten the rear overhang of the vehicle body by realizing the forward arrangement of the rear frame 40.

[0074] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be modified as appropriate within the scope of the present invention. [Explanation of symbols]

[0075] 1 Rear body structure 2 Die-casting section 3 rear wheels 4 Drive Unit 10 Rear wheel house 11 Bulging part (rear wheel house main body) 20 Rear floor panel 21 Upper wall (rear floor panel main body) 22 Front wall (rear floor panel main body) 23 First lower wall portion (rear floor panel main body portion) 24 Rear wall (rear floor panel main body) 25 Second lower wall portion (rear floor panel main body) 25a Notch 26 Rear frame connection 26a Opposite wall 26b External wall 26c Inner wall 26d Lower wall part 27 Drive unit mounting part 31 Left and right ribs 32 Front and rear ribs 32a, 32c Front and rear ribs (load transfer ribs, upper ribs) 33 Annular rib 34 Opposing ribs 36 Left and right ribs 37 Front and rear ribs 37a, 37b, 37c Front and rear ribs (load transfer ribs, lower ribs) 38 Annular rib 39 Reinforcing rib 40 rear frame 41 Front end X jig

Claims

1. A vehicle body rear structure including a rear wheel house portion and a rear frame connecting portion to which a rear frame is connected, which are integrally formed by die casting, The rear wheel house portion includes a bulging portion that bulges inward in the vehicle width direction to cover the rear wheel, At least a portion of the rear frame connecting portion is disposed forward of the rear end portion of the bulging portion. A vehicle rear structure characterized by:

2. The rear frame connecting portion is provided at a position where the vehicle width direction distance from the vehicle body end portion on the opposite side of the rear frame connecting portion in the vehicle width direction is within 70% of the overall vehicle width.

2. The vehicle rear structure according to claim 1.

3. The rear floor panel portion includes opposing ribs extending in the front-rear direction, The opposing rib is provided at a position facing the front end of the rear frame.

2. The vehicle rear structure according to claim 1.

4. A pair of left and right rear wheel house portions; a rear floor panel portion connecting the pair of left and right rear wheel house portions; are integrally formed by die-casting, The rear frame connecting portion is provided in the rear floor panel portion.

2. The vehicle rear structure according to claim 1.

5. Between the pair of left and right rear wheel house portions, a rear end portion of the rear floor panel portion is located forward of rear end portions of the bulging portions of the pair of left and right rear wheel house portions, The rear frame connecting portion is provided in front of the rear end portion of the rear floor panel portion.

5. The vehicle rear structure according to claim 4.

6. The front end of the rear frame is located forward of the rear end of the drive unit disposed between the pair of left and right rear frames.

2. The vehicle rear structure according to claim 1.

7. The rear frame connecting portion is provided inward in the vehicle width direction from the inner end portion in the vehicle width direction of the bulging portion.

2. The vehicle rear structure according to claim 1.

8. The rear frame connecting portion is configured to be able to connect the rear frame from the vehicle exterior side of the rear wheel house portion.

2. The vehicle rear structure according to claim 1.

9. The rear frame connecting portion is disposed at a position overlapping with the rear wheel in a side view.

2. The vehicle rear structure according to claim 1.

Images